What Is the Self-Discharge Rate of Batteries

Self-discharge — also known as charge retention capacity — is the loss of stored energy that occurs when a battery sits in open-circuit state. Even without a load, a battery slowly loses charge due to internal side reactions.

Quality VRLA and LiFePO4 batteries are engineered for very low self-discharge: a well-made AGM or gel cell typically loses only 1–3% per month at 20°C, while lithium chemistry can retain charge for many months. Higher temperatures accelerate self-discharge significantly.

For telecom and solar backup systems that may sit idle for long periods, low self-discharge translates directly into reliability — the battery is ready when the grid fails. Specify self-discharge performance in your procurement checklist and store batteries in cool, dry conditions.